evolution of a design

I've been really obsessing over doing my own murals lately.  I worked on these designs for a proposal in my sketchbook over the weekend.  The ideas start out really flat then gain some depth.   My favorites are 4 and 7.  I've only done 1 or 2 murals/signs in spray paint but I think it would be really cool to try to make some of those textures you get with pencil and marker with the spray paint.  

  

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